In electronic appliances containing modular jacks, various types of filters are used to reduce or eliminate noise. Such filters may include a three terminal capacitor or a common mode choke coil. A disadvantage in the use of such filters is that they may complicate the production of the circuit board. A need, therefore, has been perceived for providing a simple means of filtering noise in modular jacks.
The use of an integral ferrite element for this purpose is proposed in Japanese Patent Publication 64-2273. This reference discloses a modular jack having a modular insert installed in a casing. The body of the insert is formed with ferrite, and on one side of the insert body insert holes are formed for introducing connecting lines to be connected to respective contact springs.
While this reference would appear to simplify the apparatus used for noise filtering in modular jacks, a need for further increasing the compactness of such modular jacks with integral ferrite elements exists. U.S. Pat. No. 5,456,619 discloses a filtered modular jack assembly having an outer insulative housing with open front and rear sides. A ferrite element with vertical conductive wires is positioned adjacent the rear end, and an elongated insulative insert is superimposed over the ferrite element. The insulative insert is fixed to the housing, and the conductive wire extends vertically from the ferrite element over the upper side of the insert to its terminal end and then bends downwardly and rearwardly to rest on the top surface of an interior medial wall in the housing. While this reference discloses an invention which increases compactness, a need still exists for a jack which can achieve such compactness while using alternate types of filtering elements which arc not adapted to be mounted in the same way as the ferrite element.
A need also exists for such a compact jack that can accept multiple types of contacts for contacting respective contact-receiving elements on an underlying substrate. In addition, a need exists for such a compact jack with contacts that are spaced from an outer jack shield, wherein shorting to the jack shield or sparking to the jack shield during periods of high voltage is minimize or eliminated.